The biomechanical variables involved in the aetiology of iliotibial band syndrome in distance runners – A systematic review of the literature

The aim of this literature review was to identify the biomechanical variables involved in the aetiology of iliotibial band syndrome (ITBS) in distance runners. An electronic search was conducted using the terms “iliotibial band” and “iliotibial tract”.The results showed that runners with a history of ITBS appear to display decreased rear foot eversion, tibial internal rotation and hip adduction angles at heel strike while having greater maximum internal rotation angles at the knee and decreased total abduction and adduction range of motion at the hip during stance phase. They further appear to experience greater invertor moments at their feet, decreased abduction and flexion velocities at their hips and to reach maximum hip flexion angles earlier than healthy controls. Maximum normalised braking forces seem to be decreased in these athletes. The literature is inconclusive with regards to muscle strength deficits in runners with a history of ITBS. Prospective research suggested that greater internal rotation at the knee joint and increased adduction angles of the hip may play a role in the aetiology of ITBS and that the strain rate in the iliotibial bands of these runners may be increased compared to healthy controls.A clear biomechanical cause for ITBS could not be devised due to the lack of prospective research.     

Gender differences in gait kinematics in runners with iliotibial band syndrome

Atypical running gait biomechanics are considered a primary factor in the etiology of iliotibial band syndrome (ITBS). However, a general consensus on the underpinning kinematic differences between runners with and without ITBS is yet to be reached. This lack of consensus may be due in part to three issues: gender differences in gait mechanics, the preselection of discrete biomechanical variables, and/or relatively small sample sizes. Therefore, this study was designed to address two purposes: (a) examining differences in gait kinematics for male and female runners experiencing ITBS at the time of testing and (b) assessing differences in gait kinematics between healthy gender‐ and age‐matched runners as compared with their ITBS counterparts using waveform analysis. Ninety‐six runners participated in this study: 48 ITBS and 48 healthy runners. The results show that female ITBS runners exhibited significantly greater hip external rotation compared with male ITBS and female healthy runners. On the contrary, male ITBS runners exhibited significantly greater ankle internal rotation compared with healthy males. These results suggest that care should be taken to account for gender when investigating the biomechanical etiology of ITBS.     

Lower extremity mechanics of iliotibial band syndrome during an exhaustive run

Injury patterns in distance running may be related to kinematic adjustments induced by fatigue. The goal was to measure changes in lower extremity mechanics during an exhaustive run in individuals with and without a history of iliotibial band syndrome (ITBS). Sixteen recreational runners ran to voluntary exhaustion on a treadmill at a self-selected pace. Eight runners had a history of ITBS. Twenty-three reflective marker positions were recorded by an eight-camera 120 Hz motion capture system. Joint angles during stance phase were exported to a musculoskeletal model (SIMM) with the iliotibial band (ITB) modeled as a passive structure to estimate strain in the ITB. For ITBS runners, at the end of the run: (1) knee flexion at heel-strike was higher than control (20.6 degrees versus 15.3 degrees, p=0.01); (2) the number of knees with predicted ITB impingment upon the lateral femoral epicondyle increased from 6 to 11. Strain in the ITB was higher in the ITBS runners throughout all of stance. Maximum foot adduction in the ITBS runners was higher versus control at the start of the run (p=0.003). Maximum foot inversion (p=0.03) and maximum knee internal rotation velocity (p=0.02) were higher versus control at the end of the run. In conclusion, ITB mechanics appear to be related to changes in knee flexion at heel-strike and internal rotation of the leg. These observations may suggest kinematic discriminators for clinical assessment.     

Effects of hamstring stretching on passive muscle stiffness vary between hip flexion and knee extension maneuvers

The purpose of this study was to examine whether the effects of hamstring stretching on the passive stiffness of each of the long head of the biceps femoris (BFl), semitendinosus (ST), and semimembranosus (SM) vary between passive knee extension and hip flexion stretching maneuvers. In 12 male subjects, before and after five sets of 90 s static stretching, passive lengthening measurements where knee or hip joint was passively rotated to the maximal range of motion (ROM) were performed. During the passive lengthening, shear modulus of each muscle was measured by ultrasound shear wave elastography. Both stretching maneuvers significantly increased maximal ROM and decreased passive torque at a given joint angle. Passive knee extension stretching maneuver significantly reduced shear modulus at a given knee joint angle in all of BFl, ST, and SM. In contrast, the stretching effect by passive hip flexion maneuver was significant only in ST and SM. The present findings indicate that the effects of hamstring stretching on individual passive muscles’ stiffness vary between passive knee extension and hip flexion stretching maneuvers. In terms of reducing the muscle stiffness of BFl, stretching of the hamstring should be performed by passive knee extension rather than hip flexion.     

Iliotibial band syndrome: an examination of the evidence behind a number of treatment options

Iliotibial band (ITB) syndrome (ITBS) is a common cause of distal lateral thigh pain in athletes. Treatment often focuses on stretching the ITB and treating local inflammation at the lateral femoral condyle (LFC). We examine the area's anatomical and biomechanical properties. Anatomical studies of the ITB of 20 embalmed cadavers. The strain generated in the ITB by three typical stretching maneuvers (Ober test; Hip flexion, adduction and external rotation, with added knee flexion and straight leg raise to 30°) was measured in five unembalmed cadavers using strain gauges. Displacement of the Tensae Fasciae Latae (TFL)/ITB junction was measured on 20 subjects during isometric hip abduction. The ITB was uniformly a lateral thickening of the circumferential fascia lata, firmly attached along the linea aspera (femur) from greater trochanter up to and including the LFC. The microstrain values [median (IQR)] for the OBER [15.4(5.1–23.3)me], HIP [21.1(15.6–44.6)me] and SLR [9.4(5.1–10.7)me] showed marked disparity in the optimal inter‐limb stretching protocol. HIP stretch invoked significantly (Z=2.10, P=0.036) greater strain than the SLR. TFL/ITB junction displacement was 2.0±1.6 mm and mean ITB lengthening was <0.5% (effect size=0.04). Our results challenge the reasoning behind a number of accepted means of treating ITBS. Future research must focus on stretching and lengthening the muscular component of the ITB/TFL complex.     

Differences in kinematics of single leg squatting between anterior cruciate ligament-injured patients and healthy controls

Seventy to eighty percent of all anterior cruciate ligament (ACL) injuries are due to non-contact injury mechanisms. It has been reported that the majority of injuries due to single leg landing come from valgus positioning of the lower leg. Preventing valgus positioning during single leg landing is expected to help reduce the number of ACL injuries. We found that many ACL-deficient patients cannot perform stable single leg squatting. Therefore, we performed 3D motion analysis of the single-legged half squat for ACL-injured patients to evaluate its significance as a risk factor for ACL injuries. We evaluated the relative angles between the body, thigh, and lower leg using an electromagnetic device during single leg half squatting performed by 63 ACL-injured patients (32 males, 31 females) the day before ACL reconstruction and by 26 healthy control subjects with no knee problems. The uninjured leg of ACL-injured male subjects demonstrated significantly less external knee rotation than that of the dominant leg of the male control. The uninjured leg of ACL-injured female subjects demonstrated significantly more external hip rotation and knee flexion and less hip flexion than that of the dominant leg of the female control. Comparing injured and uninjured legs, the injured leg of male subjects demonstrated significantly less external knee and hip rotation, less knee flexion, and more knee varus than that of the uninjured leg of male subjects. The injured leg of female subjects demonstrated more knee varus than that of the uninjured leg of female subjects. Regarding gender differences, female subjects demonstrated significantly more external hip rotation and knee valgus than male subjects did in both the injured and uninjured legs (P < 0.05). The current kinematic study exhibited biomechanical characteristics of female ACL-injured subjects compared with that of control groups. Kinematic correction during single leg half squat would reduce ACL reinjury in female ACL-injured subjects.     

Kinematics and electromyography of landing preparation in vertical stop-jump: risks for noncontact anterior cruciate ligament injury

BACKGROUND: Biomechanical analysis of stop-jump tasks has demonstrated gender differences during landing and a potential increase in risk of noncontact anterior cruciate ligament injury for female athletes. Analysis of landing preparation could advance our understanding of neuromuscular control in movement patterns and be applied to the development of prevention strategies for noncontact anterior cruciate ligament injury. HYPOTHESIS: There are differences in the lower extremity joint angles and electromyography of male and female recreational athletes during the landing preparation of a stop-jump task. STUDY DESIGN: Controlled laboratory study. METHODS: Three-dimensional videographic and electromyographic data were collected for 36 recreational athletes (17 men and 19 women) performing vertical stop-jump tasks. Knee and hip angular motion patterns were determined during the flight phase before landing. RESULTS: Knee and hip motion patterns and quadriceps and hamstring activation patterns exhibited significant gender differences. Female subjects generally exhibited decreased knee flexion (P = .001), hip flexion (P = .001), hip abduction (P = .001), and hip external rotation (P = .03); increased knee internal rotation (P = .001); and increased quadriceps activation (P = .001) compared with male subjects. Female subjects also exhibited increased hamstring activation before landing but a trend of decreased hamstring activation after landing compared with male subjects (P = .001). CONCLUSION: Lower extremity motion patterns during landing of the stop-jump task are preprogrammed before landing. Female subjects prepared for landing with decreased hip and knee flexion at landing, increased quadriceps activation, and decreased hamstring activation, which may result in increased anterior cruciate ligament loading during the landing of the stop-jump task and the risk for noncontact ACL injury.     

The effect of active warm-up and stretching on the flexibility of adolescent soccer players

AIM: The purpose of the investigation was to examine in field conditions the acute effects of passive stretching after a general warming-up bout as well as the effects of passive stretching alone. METHODS: Eighteen adolescent team soccer players participated in this study performing 3 different flexibility-training protocols in separate training sessions. In the first treatment stretching protocol a general warm-up was performed where subjects jogged for 20 minutes. The second treatment stretching protocol consisted of the same general warm-up followed by passive stretching of the lower extremities and the trunk, whereas the third and final treatment stretching protocol consisted of passive stretching alone, without any jogging. Passive range of joint motion was examined in hip flexion, hip extension, hip abduction, ankle dorsiflexion, knee flexion and trunk flexion using a goniometer and a flexometer. RESULTS: The general warming-up session induced a significantly increased range of motion only at the ankle dorsiflexion joint (P<0.05). Results also suggest that passive stretching alone and passive stretching after a general warming-up bout both induced a significantly increased range in all lower extremity joints and trunk flexion (P<0.001). CONCLUSIONS: Improvements in flexibility are observed after passive muscle elongation, irrespective of warming-up.     

Effects of two different knee tape procedures on lower‐limb kinematics and kinetics in recreational runners

The purpose of this study was to compare the effects of Mulligan's tape (MT) and kinesio tape (KT) with no tape (NT) on hip and knee kinematics and kinetics during running. Twenty‐nine female recreational runners performed a series of ‘run‐throughs’ along a 10‐m runway under the three taping conditions. Two force plates and a 14‐camera Vicon motion analysis system (Oxford Metrics, Inc., Oxford, UK) captured kinematic and kinetic data for each dependent variable from ground contact to toe off. Comparisons of each dependent variable under three taping conditions were assessed through Statistical Package for the Social Sciences (SPSS; SPSS, Inc., Chicago, Illinois, USA; P‐value < 0.01) using repeated measure analyses of variance. For each dependent variable with a P‐value < 0.01, repeated measures with pairwise comparisons and Bonferroni adjustment were conducted to compare the three taping conditions. MT induced a significant reduction in anterior and posterior hip forces, knee flexion angular velocity, knee extensor moments, and hip flexion and extension moments compared with NT and KT (P = 0.001). There was no difference in hip or knee, kinematics or kinetics, between KT and NT (P = 1.000). MT appears to influence hip and knee biomechanics during running in an asymptomatic sample, whereas KT appeared to be biomechanically not different from NT.     

Do hip strength,flexibility and running biomechanics predict dynamic valgus in female recreational runners?

BackgoundDynamic valgus has been the focus of many studies to identify its association to an increased risk of running-related injuries. However, it is not known which physical and biomechanical variables are associated with this movement dysfunction. Research question: This study aimed to test the correlation between strength, flexibility and biomechanical variables and dynamic valgus in female runners.MethodsTwenty-nine healthy females ran on a treadmill at 2.92 m/s and performed strength, range of motion and endurance tests. Pelvic, hip and ankle kinematics were measured with a 3D motion analysis system. Six multiple linear regression models were used to identify the ability of physical and biomechanical variables to predict excursion and peak of contralateral pelvic drop, hip adduction and internal rotation.ResultsContralateral pelvic drop and hip adduction were positively correlated to ankle eversion and step cadence. Hip internal rotation had a negative correlation with ankle eversion. Despite significance, predictor variables explained less than 30% of dynamic valgus variance during running. No interest variable had significant correlation with the hip strength and hip and ankle passive range of motion.SignificanceThe results showed that distal joint kinematics and spatiotemporal variables should be considered during biomechanical running analysis to identify their possible relationship with joint overload caused by dynamic valgus. Caution should be taken when linking hip disorders during running to posterolateral hip strength and stiffness, core endurance, and ankle dorsiflexion range of motion since no correlation occurred amongstthese variables in this sample of female runners.     

Kinematic risk factors for lower limb tendinopathy in distance runners: A systematic review and meta-analysis

IntroductionAbnormal kinematics have been implicated as one of the major risk factors for lower limb tendinopathy (LLT).ObjectiveTo systematically review evidence for kinematic risk factors for LLT in runners.MethodsIndividual electronic searches in PubMed, EMBASE and Web of Science were conducted. Two reviewers screened studies to identify observational studies reporting kinematic risk factors in runners with LLT compared to healthy controls. The Down and Black appraisal scale was applied to assess quality. A meta-analysis was performed provided that at least two studies with similar methodology reported the same factor.ResultsTwenty-eight studies were included: Achilles tendinopathy (AT) (9), iliotibial band syndrome (ITBS) (17), plantar fasciopathy (PF) (2), patellar tendinopathy (PT) (1), posterior tibial tendon dysfunction (PTTD) (1). Eighteen studies were rated high-quality and ten medium-quality. The meta-analyses revealed strong evidence of higher peak knee internal rotation, moderate evidence of lower peak rearfoot eversion and knee flexion at heel strike and greater peak hip adduction in runners with ITBS. Very limited evidence revealed higher peak ankle eversion in runners with PF and PTTD or higher peak hip adduction in PT.SignificancePeak rearfoot eversion was the only factor reported in all included LLTs; it is a significant factor in ITBS, PT and PTTD but not in AT and PF. More prospective studies are needed to accurately evaluate the role of kinematic risk factors as a cause of LLT. Taken together, addressing rearfoot kinematic and kinematic chain movements accompanied by peak eversion should be considered in the prevention and management of LLT.     

Lower extremity joint position sense in runners with and without a history of knee overuse injury

Kinematic and kinetic analyses are routinely implemented to determine if gait differences exist between runners with and without a history of knee injury. Hip and knee kinematic differences have been reported between knee injured and non-injured runners. Yet, there is no consensus on whether these differences are the primary variables contributing to knee injury. Furthermore, there may be additional underlying factors that contribute to the development of injury that cannot be determined by gait analysis. The purpose of this investigation was to determine if joint position sense differences exist in runners with and without a history of knee overuse injury. Sagittal plane knee and hip joint position sense was measured in 13 runners with a history of knee overuse injury and 13 runners with no history of knee overuse injury. Absolute joint position replication error was measured during both a weight bearing and a non-weight bearing condition. Joint position replication errors at each joint were compared among groups and task using a two-way ANOVA with joint task as the repeated measure. Knee and hip joint replication errors were similar between both groups. The weight bearing and non-weight bearing tasks resulted in similar joint position replication errors. There were no interaction effects. In conclusion, knee flexion and hip adduction joint position sense is similar in runners with and without a history of knee overuse injury. Therefore, joint position sense measured via weight bearing and non-weight bearing joint position replication tasks may not play an important role in the development of knee overuse injury.     

The immediate effects of Kinesio Taping on running biomechanics,muscle activity,and perceived changes in comfort,stability and running performance in healthy runners,and the implications to the management of Iliotibial band syndrome

BackgroundKinesio Taping is frequently used in the management of lower limb injuries, and has been shown to improve pain, function, and running performance. However, little is known about the effects of Kinesio Taping on running biomechanics, muscle activity, and perceived benefits.Research questionThis study aimed to explore the immediate effects of Kinesio Taping on lower limb kinematics, joint moments, and muscle activity, as well as perceived comfort, knee joint stability, and running performance in healthy runners.MethodsTwenty healthy participants ran at a self-selected pace along a 20-metre runway under three conditions; no tape (NT), Kinesio Tape with tension (KTT), and Kinesio tape without tension (KTNT). Comparisons of peak hip, knee angles and moments, and EMG were analysed during the stance phase of running.ResultsKTT exhibited significant increases in peak hip flexion, peak hip abduction and hip external rotation compared to NT. Moreover, the KTT condition showed a trend towards a decrease in peak hip internal rotation and adduction angle compared to the NT condition. EMG results showed that Tensor Fascia Latae activity decreased with KTT compared with NT, and Gluteus Maximus activity reduced with KTNT when compared with NT. Ten of the 20 participants indicated important improvements in the comfort score, six participants in the knee stability score, and seven participants in the running performance score when using KTT.SignificanceThese results suggest that changes in running biomechanics previously associated with ITBS can be improved with the application of kinesio tape, with the greatest effect seen with the application of kinesio tape with tension. Perceived improvements were seen in comfort, stability and running performance, however these benefits were only seen in half the participants. Further work is required to explore the biomechanical effects and perceived benefits in different patient groups.     

Effects of a functional knee brace on the biomechanics of running.

The purpose of the study was to assess the biomechanical effects of a functional knee brace on joint moments of force and joint powers in the lower extremity during the stance phase of running in subjects with a previous ACL injury. Sagittal-plane film records and ground reaction force data were obtained from five previously injured subjects running with and without a functional knee brace and from five healthy subjects running without the brace. Inverse dynamics were performed on these data to obtain the moments of force and joint powers. The angular impulse in the extensor direction was assessed from each moment of force curve, and the work performed during selected portions of the stance phase was assessed from the joint power curves. ANOVA techniques on these variables indicated no significant differences between the brace and no-brace conditions in the previously injured subjects. In comparison with the healthy runners, the previously injured subjects had, on average, 49% and 32% greater extensor angular impulse about the hip and ankle (both P less than 0.05). In contrast, the healthy runners had, on average, 233% greater (P less than 0.05) extensor angular impulse about the knee. The corresponding negative and positive work performed at the knee were 321% and 191% larger (both P less than 0.05) in the healthy runners. The reduction in the extensor moment of force about the knee and the increase in the moments of force about the hip and ankle in the previously injured subjects reduced the stresses on the ACL and tibia while at the same time enabling them to run at the required speed.     

Gait kinematics of age-stratified hip replacement patients--a large scale, long-term follow-up study

Three-dimensional gait analysis data from 134 patients attending routine 10-year post-operative review clinics is presented. Patients were divided into five age groups-54-64 years, 65-69 years, 70-74 years, 75-79 years and over 80 years. A group of 10 normal elderly subjects was also tested. All age groups displayed reduced range of hip flexion/extension, range of knee flexion extension, maximum hip extension and range of hip abduction/adduction and reduced velocity and step length compared to the normal elderly group. However, there was no difference in gait kinematics between the age groups. Patients over 80 years of age displayed significantly reduced range of sagittal plane ankle motion, but this is unlikely to be secondary to hip joint restriction and more likely due to reduced walking speed associated with very elderly subjects. This study reveals that even the youngest hip replacement patients do not attain normal gait kinematics 10-year post-operatively and that muscle atrophy and residual stiffness may influence patient kinematics many years post-operation.     

DOMS-associated changes in ankle and knee joint dynamics during running

PURPOSE: The purpose of this study was to determine whether leg mechanics change due to DOMS by examining ankle and knee joint kinematics and stiffness before and after a down hill run. METHODS: Sagittal plane kinematics were recorded with high-speed (120 Hz) video at a speed representing 75% of VO2peak of nine well-trained male runners before (RE1) and 48 h after (RE2) a 30-min downhill run. From the recorded video, 10-12 consecutive strides were digitized, and the following variables were calculated for each stride: ankle and knee range of motion (ROM), ankle and knee peak angular velocity, ankle and knee stiffness, and leg vertical stiffness. A repeated measures ANOVA was calculated for each variable (alpha = 0.05). RESULTS: Both knee and ankle ROM during stance decreased with DOMS, but otherwise there were few changes in ankle mechanics with DOMS. Knee stiffness tended to increase during the early portion of stance (from initial stance to maximum angular velocity of flexion) with DOMS, immediately followed by a decrease (to maximum knee flexion) in stiffness. Changes in knee stiffness caused vertical leg stiffness to increase for the initial portion of stance with DOMS. CONCLUSION: Knee mechanics changed such that the knee stiffness increased at initial stance, resulting in an increase in vertical leg stiffness. This change in knee stiffness possibly serves as a protective mechanism to prevent further damage or pain in the knee extensor musculature.     

Uphill and downhill walking in unilateral lower limb amputees

OBJECTIVE: To study adjustment strategies in unilateral amputees in uphill and downhill walking. DESIGN: Observational cohort study. SUBJECTS: Seven transfemoral, 12 transtibial unilateral amputees and 10 able-bodied subjects. METHODS: In a motion analysis laboratory the subjects walked over a level surface and an uphill and downhill slope. Gait velocity and lower limb joint angles were measured. RESULTS: In uphill walking hip and knee flexion at initial contact and hip flexion in swing were increased in the prosthetic limb of transtibial amputees. In downhill walking transtibial amputees showed more knee flexion on the prosthetic side in late stance and swing. Transfemoral amputees were not able to increase prosthetic knee flexion in uphill and downhill walking. An important adjustment strategy in both amputee groups was a smaller hip extension in late stance in uphill and downhill walking, probably related with a shorter step length. In addition, amputees increased knee flexion in early stance in the non-affected limb in uphill walking to compensate for the shorter prosthetic limb length. In downhill walking fewer adjustments were necessary, since the shorter prosthetic limb already resulted in lowering of the body. CONCLUSION: Uphill and downhill walking can be trained in rehabilitation, which may improve safety and confidence of amputees. Prosthetic design should focus on better control of prosthetic knee flexion abilities without reducing stability.     

Stretching exercise and soccer: effect of stretching on range of motion in the lower extremity in connection with soccer training

Forty-eight players from four senior, male soccer teams were tested for ranges of motion (ROM) in the lower extremity before, immediately after, and 24 h after different forms of soccer training. The players were tested after regular soccer training (A), after soccer training with contract-relax stretching prior to beginning the session (B), and after soccer training with stretching added at the end of the program (C). Each training session lasted 1.5 h. In group A all six ROMs were decreased 24 h after the training. In group B the only change in ROM noted was an increase in knee flexion directly after the training. In group C there was an increase in hip extension, hip flexion, and knee flexion directly after the training.